The preliminary hearing for Cosmo DiNardo, the man who confessed to the killings of four young men in Bucks County, Pennsylvania, was postponed from July 31. DiNardo and his cousin, Sean Kratz, were now set to appear before a district judge in Doylestown, Pennsylvania Sept. 7.

Kratz and DiNardo remained behind bars after being unable to post bail following their arrests.

Read: Everything We Know About Murders Of Four Missing Pennsylvania Men

DiNardo, 20, was charged with four counts of murder after confessing to killing Jimi Tar Patrick, 19, Dean Finocchiaro, 19, Tom Meo, 21, and Mark Sturgis, 22, earlier in July. Kratz, also 20, was charged with criminal homicide in three of the deaths. DiNardo confessed to the killings just a few days after all four boys went missing. He told authorities he lured them to his family’s 68-acre farm under the guise of selling them marijuana and then killed them with Kratz’s help.

In exchange for the confession, prosecutors agreed not to seek the death penalty against DiNardo. DiNardo reportedly has a history of schizophrenia and has been involuntary committed to a psychiatric facility in the past.

In the lead up to the preliminary hearing in September, authorities were working to determine whether there was any truth to DiNardo’s claim that he had killed others in the past. As part of his confession, DiNardo reportedly told police that he had killed two people in Philadelphia when he was younger. Police said last week they had not yet had a chance to speak with DiNardo, verify or disprove his claims.

“Given what he was already been accused of, it’s certainly a possibility,” Philadelphia Police Commissioner Richard Ross told WCAU Tuesday. “We would be remiss if we didn’t investigate further.”

DiNardo revealed the locations of all four men’s bodies as part of his confession. Authorities were able to locate the remains on his parents’ expansive property in Solebury Township in Pennsylvania.

Read: Cosmo DiNardo Motive: Why Were Four Missing Pennsylvania Men Killer?

Kratz retained attorney Abby Leeds to represent him in the case Tuesday. Leeds told reporters Kratz’s family sympathized with the families of the victims but that she would give Kratz a “vigorous and dedicated defense.”